Study on the Fatigue Analysis Technology of the Control Rod Drive Mechanism Considering the Coolant Environment

3-D virtual analysis system to analyze the motion of Control Rod Drive Mechanism (CRDM) was developed. The analysis system consists of 3-D model established per the actual dimensions and interfaces of CRDM parts and a routine to calculate forces acting on the mechanism, and was verified by mock-up test using equipment same to actual product. The analysis system is useful for functional evaluation in maintenance or to factor out root causes in case of malfunction of CRDM.

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Long-term stability of Sm/sub 2/Co/sub 17/-type magnets for control rod drive mechanism (CRDM) in a nuclear reactor

IEEE Transactions on Magnetics ◽

10.1109/20.489599 ◽

1995 ◽

Vol 31 (6) ◽

pp. 3653-3655 ◽

Cited By ~ 2

Author(s):

H. Iida ◽

S. Imayoshi ◽

K. Morimoto ◽

M. Watanabe ◽

N. Komada ◽

...

Keyword(s):

Nuclear Reactor ◽

Control Rod ◽

Drive Mechanism ◽

Term Stability ◽

Long Term Stability

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Effects of Weld Geometry on Residual Stress and Crack Driving Force for Centerhole Control Rod Drive Mechanism Nozzles: Part I — Weld Residual Stress

Volume 6: Materials and Fabrication ◽

10.1115/pvp2005-71077 ◽

2005 ◽

Cited By ~ 1

Author(s):

Wentao Cheng ◽

David L. Rudland ◽

Gery Wilkowski ◽

Wallace Norris

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Driving Force ◽

Nuclear Regulatory Commission ◽

Crack Driving Force ◽

Control Rod ◽

Drive Mechanism ◽

Weld Geometry ◽

Weld Residual Stress ◽

Regulatory Commission

The U.S. Nuclear Regulatory Commission (NRC) has undertaken a program to assess the integrity of control rod drive mechanism (CRDM) nozzles in existing plants that are not immediately replacing their RPV heads. This two-part paper summarizes some of the efforts undertaken on the behalf of the U.S.NRC for the development of detailed residual stress and circumferential crack-driving force solutions to be used in probabilistic determinations of the time from detectable leakage to failure. In this first paper, the finite element (FE) simulations were conducted to investigate the effects of weld geometry on the residual stresses in the J-weld for a centerhole CRDM nozzle. The variables of weld geometry included three weld heights (weld sizes) and three groove angles for each weld height while keeping the same weld size. The analysis results indicate that the overall weld residual stress decreases as the groove angle increases and higher residual stress magnitude is associated with certain weld height. The results also reveal that the axial residual stresses in the Alloy 600 tube are very sensitive to the weld height, and that the tube hoop stresses above the J-weld root increase with the increasing weld height.

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Development of In-vessel Type Control Rod Drive Mechanism for Marine Reactor

Journal of Nuclear Science and Technology ◽

10.1080/18811248.2001.9715067 ◽

2001 ◽

Vol 38 (7) ◽

pp. 557-570 ◽

Cited By ~ 14

Author(s):

Toshihisa ISHIDA ◽

Shou IMAYOSHI ◽

Tsutomu YORITSUNE ◽

Hiroshi NUNOKAWA ◽

Masa-aki OCHIAI ◽

...

Keyword(s):

Control Rod ◽

Drive Mechanism

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Reseach on ultrasonic inspection of control rod drive mechanism housing weld in Chinese Evolutionary Pressurized Reactor nuclear power plant

2014 IEEE Far East Forum on Nondestructive Evaluation/Testing ◽

10.1109/fendt.2014.6928247 ◽

2014 ◽

Author(s):

Huaidong Chen ◽

Zhe Yu ◽

Weiqiang Wang ◽

Guanbing Ma ◽

Maocheng Hong

Keyword(s):

Power Plant ◽

Nuclear Power Plant ◽

Nuclear Power ◽

Ultrasonic Inspection ◽

Control Rod ◽

Drive Mechanism

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Dynamic Response Analysis of Control Rod Drive Mechanism Under the Stepping Impact Force for Nuclear Power Plants

Volume 2: Plant Systems, Structures, and Components; Safety and Security; Next Generation Systems; Heat Exchangers and Cooling Systems ◽

10.1115/icone20-power2012-54359 ◽

2012 ◽

Author(s):

Xiaoyao Shen ◽

Yongcheng Xie

Keyword(s):

Dynamic Response ◽

Nuclear Power ◽

Power Plants ◽

Structural Integrity ◽

Impact Force ◽

Response Analysis ◽

Control Rod ◽

Drive Mechanism ◽

Finite Element Software ◽

The Impact

The control rod drive mechanism (CRDM) is an important safety-related component in the nuclear power plant (NPP). When CRDM steps upward or downward, the pressure-containing housing of CRDM is shocked axially by an impact force from the engagement of the magnetic pole and the armature. To ensure the structural integrity of the primary coolant loop and the functionality of CRDM, dynamic response of CRDM under the impact force should be studied. In this manuscript, the commercial finite element software ANSYS is chosen to analyze the nonlinear impact problem. A nonlinear model is setup in ANSYS, including main CRDM parts such as the control rod, poles and armatures, as well as nonlinear gaps. The transient analysis method is adopted to calculate CRDM dynamic response when it steps upward. The impact loads and displacements at typical CRDM locations are successfully obtained, which are essential for design and stress analysis of CRDM.

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